This invention may be related to U.S. patent application Ser. No. 11/264,654, filed Oct. 31, 2005, entitled “Skin Detection Sensor,” the disclosure of which is incorporated herein in its entirety. In that application, two IR bands are directed at a target proposed to be human skin. One IR band is capable of being reflected from skin and the other is absorbed by skin. When both conditions exist, skin is detected as being present.
The invention may be related to U.S. patent application Ser. No. 10/987,806, filed Nov. 12, 2004, and entitled “Infrared and Visible Fusion Face Recognition System”. The invention may also be related to U.S. patent application Ser. No. 10/946,748, filed Nov. 12, 2004, and entitled “Infrared Face Detection and Recognition System”. These above-mentioned patent applications are incorporated herein by reference. The assignee of these patent applications is the same assignee of the present invention.
Other related patent documents may include U.S. Pat. No. 6,370,260 B1, issued Apr. 9, 2002, entitled “Near-IR Human Detector”, and by Pavlidis et al.; U.S. Pat. No. 6,718,049 B2, issued Apr. 6, 2004, entitled “Near-Infrared Disguise Detection”, and by Pavlidis et al.; and U.S. patent application Ser. No. 10/077,672, filed Feb. 15, 2002, entitled “Near-Infrared Method and System for Use in Face Detection”, and by Pavlidis et al.; all of which are incorporated herein by reference. The assignee of these patent documents is the same assignee of the present invention.
Current biometric sensors based on measuring fingerprint identity or hand geometry sensors are of significant interest to a variety of industries and applications. The security industry is constantly seeking sensors that identify certain specific persons to allow access to a secured area, a device such as a computer or other electronic equipment, or a cell phone. This industry is growing and thus is still encountering new issues.
However, biometric sensors that rely on a particular property of a person, such as a fingerprint, can be defeated. If a rubber cast or cutout of a fingerprint is used, the device will recognize the correct print, even if it is not being used by the person to whom it belongs. Photographs of irises have been used to thwart iris detection. Thus, access to secure property would be compromised.
However, biometric sensors that rely on a particular property of a person, such as a fingerprint, can be defeated. If a rubber cast or cutout of a fingerprint is used, the device will recognize the correct print, even if it is not being used by the person to whom it belongs. Photographs of irises have been used to thwart iris detection. Thus, access to secure property would be compromised. Recently it has been suggested that fingerprint sensors used for biometrics can be and have been spoofed by a variety of fake finger materials. An actual valid fingerprint is obtained, perhaps illegally, and is transferred to another material that has similar properties to human skin. When a sensor is used to validate the fingerprint, first determining if the fingerprint is on human skin, present day sensors cannot distinguish between real skin and some other materials.
One successful effort to defeat a fingerprint reader has been reported, where a finger print was taken from a glass using a digital photo of it, printing it on a transparency, and then using the print as an overlay to etch the fingerprint on to a surface. A finger was then molded using a gelatin material such as that found in Gummy Bears candy. This replicated finger tricked or defeated a fingerprint reader 80% of the times it was tested. Tests against eleven different commercially available fingerprint biometric systems resulted in a finding that all of the systems could be deceived by the Gummy Bear replicated finger.
It would be a great advance in the art if a device could be provided that would accurately identify the presence of human skin in a situation where an individual's specific and unique characteristic, such as a fingerprint, could then be recognized.
It would be another advantage in the art if the presence of human skin could be determined in a manner that prevents other materials from responding to these signals in the same manner.
Yet another advantage would be if a device could be provided that would be easy to use to permit or deny access to the biometric sensor.
Other advantages will appear hereinafter.